Cardiovascular disease (CVD), particularly coronary heart disease (CHD), is the leading cause of death in the US, with a high economic impact. Coronary artery calcium (CAC) is a known marker for CHD and a useful tool for estimating the risk of atherosclerotic cardiovascular disease (ASCVD). Although CACS is recommended for informing the decision to initiate statin therapy, the current standard requires a dedicated CT protocol, which is time-intensive and contributes to radiation exposure. Non-dedicated CT protocols can be taken advantage of to visualize calcium and reduce overall cost and radiation exposure; however, they mainly provide visual estimates of coronary calcium and have disadvantages such as motion artifacts. Artificial intelligence is a growing field involving software that independently performs human-level tasks, and is well suited for improving CACS efficiency and repurposing non-dedicated CT for calcium scoring. We present a review of the current studies on automated CACS across various CT protocols and discuss consideration points in clinical application and some barriers to implementation.

Background Cardiovascular diseases are the leading cause of death in Saudi Arabia, and cardiac risk-stratification scoring methods are critical in the primary healthcare setting to predict and potentially prevent the fatal outcomes of CVD. Therefore, this study aimed to examine the prognostic value of coronary artery calcium scoring (CACS) and other cardiac risk-stratification scores: arteriosclerotic cardiovascular disease (ASCVD) risk estimator, cardiovascular risk score (QRISK2), and triglyceride glucose index (TyG) in primary healthcare facilities in Riyadh, Saudi Arabia. Methods A retrospective cohort study was conducted at Family Medicine Clinics, and data on patient\'s demographics, medical records, and chronic illnesses obtained from the Integrated Clinical Information System (ICIS) database that were recorded between 2010 and 2019 were analyzed. We performed descriptive statistics, student\'s t-test, analysis of variance (ANOVA), Pearson correlation, Cohen\'s Kappa, and regression analyses. Results QRISK (p<0.001) and ASCVD (p<0.05) risk estimators positively correlated with the CACS score in predicting fatal and non-fatal cardiac outcomes while the TyG score had the lowest prediction ability among all the other risk estimators. CACS (OR = 1.003; 95% CI: 1.005 -1.002) (p<0.001), ASCVD (OR = 18.177; 95%CI: 214.578 - 1.540) (p=0.021), and QRISK2 (OR=154.796; 95%CI: 4137.356 - 5.792) (p=0.003) significantly predict stenosis unlike the TyG score\'s statistically insignificant prediction (p>0.05). Conclusion These findings show that ASCVD and QRISK2 are consistent with CACS and are effective risk indicators that could be used to predict cardiac-associated fatal and non-fatal cardiac events among primary care patients. This indicates that the integration of multiple risk scores, as necessary, can all contribute to more effective risk assessment and prevention of coronary artery diseases and related cardiovascular events.

Systemic lupus erythematosus (SLE) is a complex and chronic autoimmune disease that impacts multiple organ systems and presents with varying symptomatology that makes targeting treatment extremely difficult. The cardiovascular system and more specifically the coronary arteries are heavily affected by SLE causing increased atherosclerosis and subsequently increased acute coronary syndrome (ACS) and increased future cardiac events. ACS is a common occurrence in patients with SLE due to the premature development of atherosclerosis due to the dysregulation of pro-inflammatory cytokines. Calcium scoring has been effectively utilized to identify plaque burden in patients with coronary artery calcification (CAC). Calcium scoring is a score obtained from a computed tomography (CT) image using non-contrast imaging, which provides quantitative information regarding CAC and aids in assessing cardiovascular risk. A calcium score of zero Hounsfeild units can be obtained using CT calcium scoring which indicates no calcium is identified in the coronary arteries and is a strong negative risk predictor for coronary artery disease. Early screening of SLE patients with CT calcium scoring could aid in early detection and treatment subsequently leading to delay of premature coronary atherosclerosis and future cardiac events in this patient population. Multiple studies have used calcium scoring as a method to measure arterial calcification in SLE patients. The Society of Cardiovascular Imaging has now endorsed the idea of obtaining a baseline calcium artery score with a repeat progression scan in 3-5 years. Calcium scoring has also been identified as an effective initial tool for stratification and identification of possible ACS. The various advantages of early calcium scoring signify the further research needed to fully understand and implement the advantages calcium scoring has to offer patients with SLE.

To determine if coronary artery calcium (CAC) scoring using computed tomography at 80 kilovolt-peak (kVp) and 70-kVp and tube voltage-adapted scoring-thresholds allow for accurate risk stratification as compared to the standard 120-kVp protocol. We prospectively included 170 patients who underwent standard CAC scanning at 120-kVp and 200 milliamperes and additional scans with 80-kVp and 70-kVp tube voltage with adapted tube current to normalize image noise across scans. Novel kVp-adapted thresholds were applied to calculate CAC scores from the low-kVp scans and were compared to those from standard 120-kVp scans by assessing risk reclassification rates and agreement using Kendall\'s rank correlation coefficients (Τb) for risk categories bounded by 0, 1, 100, and 400. Interreader reclassification rates for the 120-kVp scans were assessed. Agreement for risk classification obtained from 80-kVp and 70-kVp scans as compared to 120-kVp was good (Τb = 0.967 and 0.915, respectively; both p < 0.001) with reclassification rates of 7.1% and 17.2%, respectively, mostly towards a lower risk category. By comparison, the interreader reclassification rate was 4.1% (Τb = 0.980, p < 0.001). Reclassification rates were dependent on body mass index (BMI) with 7.1% and 13.6% reclassifications for the 80-kVp and 70-kVp scans, respectively, in patients with a BMI < 30 kg/m2 (n = 140), and 2.9% and 7.4%, respectively, in patients with a BMI < 25 kg/m2 (n = 68). Mean effective radiation dose from the 120-kVp, the 80-kVp, and 70-kVp scans was 0.54 ± 0.03, 0.42 ± 0.02, and 0.26 ± 0.02 millisieverts. CAC scoring with reduced tube voltage allows for accurate risk stratification if kVp-adapted thresholds for calculation of CAC scores are applied.ClinicalTrials.gov NCT03637231.

UNASSIGNED: Coronary artery calcium (CAC) scoring helps determine whether patients with known coronary artery disease (CAD) should initiate medical management by predicting future cardiac event risk. CAC scoring is underutilized because many insurance companies consider it experimental. This study aimed to determine whether CAC screening of patients at risk for CAD is associated with decreased risk of myocardial infarction and improved survival.
UNASSIGNED: The TriNetX research network was used for this study. Two cohorts of 86,574 patients aged 40 to 70 years were created. All patients were diagnosed with dyslipidemia and without CAD, and the cohorts were matched for demographics, comorbidities, and statin use. One cohort had been screened with CAC scoring while the other had not. The primary outcomes of this study were myocardial infarction and overall survival at 5 years.
UNASSIGNED: Screened patients had 44% fewer myocardial infarction events at 5 years with a 76% lower risk of death.
UNASSIGNED: CAC scoring is associated with reduced risk of myocardial infarction and death in asymptomatic dyslipidemia patients and should be considered as a screening tool in these patients. The presumed mechanism for improved outcomes is that early identification of CAD results in earlier or more intensive treatment, reducing future cardiac event risk.

This study assessed the impact of cardiac motion and in-vessel attenuation on coronary artery calcium (CAC) scoring using virtual non-iodine (VNI) against virtual non-contrast (VNC) reconstructions on photon-counting detector CT. Two artificial vessels containing calcifications and different in-vessel attenuations (500, 800HU) were scanned without (static) and with cardiac motion (60, 80, 100 beats per minute [bpm]). Images were post-processed using a VNC and VNI algorithm at 70 keV and quantum iterative reconstruction (QIR) strength 2. Calcium mass, Agatston scores, cardiac motion susceptibility (CMS)-indices were compared to physical mass, static scores as well as between reconstructions, heart rates and in-vessel attenuations. VNI scores decreased with rising heart rate (p < 0.01) and showed less underestimation than VNC scores (p < 0.001). Only VNI scores were similar to the physical mass at static measurements, and to static scores at 60 bpm. Agatston scores using VNI were similar to static scores at 60 and 80 bpm. Standard deviation of CMS-indices was lower for VNI-based than for VNC-based CAC scoring. VNI scores were higher at 500 than 800HU (p < 0.001) and higher than VNC scores (p < 0.001) with VNI scores at 500 HU showing the lowest deviation from the physical reference. VNI-based CAC quantification is influenced by cardiac motion and in-vessel attenuation, but least when measuring Agatston scores, where it outperforms VNC-based CAC scoring.

UNASSIGNED: Aortic arch calcium (AAC), which is frequently detected on ungated lung computed tomography (CT) due to a large field of view, can serve as a marker of subclinical atherosclerotic burden. Our study sought to validate novel cardiac screening metrics of subclinical atherosclerosis by evaluating the inter- and intra-observer reproducibility of AAC measurements with ungated lung CT.
UNASSIGNED: The authors randomly selected 100 ungated lung CT scans from the Multi-Ethnic Study of Atherosclerosis cohort. A Bland-Altman plot analysis was used to test inter- and intra-reader reproducibility, after measuring the total arch calcium score and arch calcium volume.
UNASSIGNED: The intra-reader reproducibility for the total arch calcium score and arch calcium volume in all subjects was excellent at 99% and 97%, respectively. The inter-reader reproducibility for the total arch calcium score and volume in all subjects was similarly excellent at 97% and 96%, respectively.
UNASSIGNED: The high reproducibility of ungated lung CT suggests a potential new method of stratifying the atherosclerotic cardiovascular disease risk among patients undergoing lung CT without requiring additional scanning. This methodology helps promote routine reporting of AAC and coronary artery calcium based on millions of ungated CT images acquired for lung screening purposes.

UNASSIGNED: The combined testing for coronary artery and pulmonary diseases is of clinical interest as risk factors are shared. In this study, a novel ECG-gated tin-filtered ultra-low dose chest CT protocol (GCCT) for integrated heart and lung acquisition and the applicability of artificial intelligence (AI)-based coronary artery calcium scoring were assessed.
UNASSIGNED: In a clinical registry of 10481 patients undergoing heart and lung CT, GCCT was applied in 44 patients on a dual-source CT. Coronary calcium scans (CCS) with 120 kVp, 100 kVp, and tin-filtered 100 kVp (Sn100) of controls, matched with regard to age, sex, and body-mass index, were retrieved from the registry (ntotal=176, 66.5 (59.4-74.0) years, 52 men). Automatic tube current modulation was used in all scans. In 20 patients undergoing GCCT and Sn100 CCS, Agatston scores were measured both semi-automatically by experts and by AI, and classified into six groups (0, <10, <100, <400, <1000, ≥1000).
UNASSIGNED: Effective dose decreased significantly from 120 kVp CCS (0.50 (0.41-0.61) mSv) to 100 kVp CCS (0.34 (0.26-0.37) mSv) to Sn100 CCS (0.14 (0.11-0.17) mSv). GCCT showed higher values (0.28 (0.21-0.32) mSv) than Sn100 CCS but lower than 120 kVp and 100 kVp CCS (all p < 0.05) despite greater scan length. Agatston scores correlated strongly between GCCT and Sn100 CCS in semi-automatic and AI-based measurements (both ρ = 0.98, p < 0.001) resulting in high agreement in Agatston score classification (κ = 0.97, 95% CI 0.92-1.00; κ = 0.89, 95% CI 0.79-0.99). Regarding chest findings, further diagnostic steps were recommended in 28 patients.
UNASSIGNED: GCCT allows for reliable coronary artery disease and lung cancer screening with ultra-low radiation exposure. GCCT-derived Agatston score shows excellent agreement with standard CCS, resulting in equivalent risk stratification.

UNASSIGNED: The study investigated the accuracy of coronary artery calcium scores (CACS) and the potential for reducing radiation dose using non-gated low-dose non-contrast chest computed tomography (CT) scanning with tin filtration for one-stop screening of the lungs and heart.
UNASSIGNED: A prospective study was conducted,193 Patients received two scans for determining CACS, including an ECG-gated CT at 120 kV (ECG-gated CT), followed by a non-gated low-dose chest CT using 100 kV with tin filtration (non-gated Sn100 kV-LDCT). The Agatston score (AS), risk stratification, and radiation dose were compared between the scan types.
UNASSIGNED: There was good consistency in the AS from both an ECG-gated CT and a non-gated low-dose chest CT scan, which had a high correlation (r = 0.970). The Kappa value of risk stratification of the two scan types was 0.549. The area under the ROC curve (AUC) of the CACS was used to develop a new risk stratification standard for non-gated Sn100 kV-LDCT evaluation of CACS. In comparison to the CACS measured by ECG-gated CT, non-gated Sn100 kV-LDCT had an AUC of 0.951 and an optimal critical value of 4.6 in the low-risk category. The AUC of low-medium risk was 0.966, and the optimal critical value was 41.2. The AUC of the medium-high risk category was 0.968, and the optimal critical value was 230. The consistency in CACS measured by ECG-gated CT and non-gated Sn100 kV-LDCT had a Kappa value of 0.831. The Effective dose (ED) of non-gated Sn100 kV-LDCT and ECG-gated CT was 0.056 ± 0.017 mSv and 0.685 ± 0.455 mSv, respectively (p < 0.05).
UNASSIGNED: The Agatston score of CACS using non-gated low-dose chest CT was accurate, but there was an underestimation in risk stratification. This study developed a new risk stratification standard for non-gated Sn100 kV-LDCT evaluation of CACS, which is in closer agreement with CACS derived from ECG-gated CT scans.

OBJECTIVE: To evaluate cardiovascular risk factors and prevalent coronary artery disease (CAD) using Coronary Artery Calcium (CAC) scoring in transgender and gender-diverse (TGD) individuals receiving gender-affirming hormone therapy (GAHT) and compare the CAC scores of TGD individuals with those of the general population.
METHODS: TGD individuals aged ≥30 years, without known risk factors for cardiovascular disease (CVD), other than tobacco use and family history of CVD, on GAHT were recruited, and baseline information, including metabolic parameters, was collected. CAC scores were obtained and compared with those of a cisgender age-matched population.
RESULTS: Of 25 transwomen recruited, 24 underwent CAC scans. Of them, 2 (8.3%) had a CAC score of >0 to 99 and 1 (4.1%) had a CAC score of ≥100. Of 22 transmen recruited, 16 underwent CAC scans. Of them, 26 (12.5%) had a CAC score of >0 to 99 and none had a CAC score of ≥100. Framingham Risk Scores were not correlated with the presence of CAC.
CONCLUSIONS: The presence of CAC in this small cohort of TGD individuals on GAHT was similar to that in the cisgender age-matched population. CAC scoring is a means to assess the prevalence of CAD in TGD individuals and identify those in whom aggressive risk reduction is indicated.